CODSWALLOP

Tubulin alpha-1A chain

Homo sapiens · seed Q71U36 · 451 aa · family defined as ≥30% identity to that seed · compiled 07 October 2026

CATH and SCOP identifiers come from the RCSB's own structure annotations, which the Domains panel already reads, so these are looked up rather than guessed at.

866Entries 1,669Entities 169Constructs 34Organisms 1,580Ligand-bound
1.25 ÅBest res.
2.95 ÅMedian res.

Every figure here is counted over the whole family rather than quoted from one entry.

The reference structure

9WD9, the structure every other member of this family is superposed onto. Rendered by the RCSB and embedded here: the live app shows an interactive viewport, which a document that fetches nothing cannot.

Rendered structure of 9WD9
9WD9 at the RCSB · open it in the 3D viewer

Which residues anyone has ever seen

How many of this family's constructs contain each residue of the seed. A trough is a stretch nobody has put in a construct, which is a construct-design answer rather than a disorder one.

12254511668 constructs

Constructs, most-used first

169 distinct constructs across 866 entries. 476 polymer entities differ from the UniProt canonical sequence in some way, 25 carry a recognised expression tag and 0 carry a fusion partner.

"Differs from canonical" is not the same as "engineered". The canonical sequence is the full gene product, so a secreted protein whose structures all start after its signal peptide counts every one of them as different: lysozyme's most-used construct, residues 19–147 on 1,239 entities, is simply the mature protein. Read the construct column below for what was actually done, rather than this count.

EntitiesLengthBest (Å)Best entryWhat was made
394 451 1.70 8QL2 matches the canonical sequence
337 445 1.52 6S8K matches the canonical sequence
109 445 2.21 7L05 matches the canonical sequence
66 450 1.80 4I4T residues 1-450
46 440 2.25 6S9E residues 1-440
40 431 2.37 8YUA residues 1-431
33 451 2.26 9WD9 matches the canonical sequence
33 451 3.50 1JFF L136S, S232G, I265G +2 more
27 444 2.21 9M1M matches the canonical sequence
22 445 2.80 8SH7 matches the canonical sequence
21 451 2.88 7X4N matches the canonical sequence
19 445 3.60 7ZCW T55A, M170V, S296A +1 more
18 451 3.57 8RX1 matches the canonical sequence
13 445 2.50 5KX5 matches the canonical sequence
12 426 3.62 6KIQ residues 2-427
12 427 2.80 9DUQ residues 1-427
12 438 2.10 7TTF residues 1-438
12 452 8.20 2XRP V7I, L114I, L136S +5 more
12 456 2.66 8VT7 TEV site
11 426 3.20 9KBW residues 1-426
11 443 1.75 7PJE matches the canonical sequence
11 450 1.80 6S8L matches the canonical sequence
10 443 3.10 8GLV matches the canonical sequence
10 449 1.75 7PJE matches the canonical sequence
10 451 3.10 8GLV matches the canonical sequence

Showing the 25 most-used of 169.

Positions people deliberately mutate

Columns where the wild-type residue still dominates but a real minority carries something else, which is a different question from "what varies across species".

Q358I 58% I265L 58% L136Q 58% V440A 57% T150G 56% A270P 56% C4I 56% Q128S 56% T94F 56% V437D 56% V14N 56% F141L 56% A389K 56% S48R 55% M154I 55% T271G 55% V275L 55% E168T 55% T194L 55% Q301M 55% T193Q 55% V204I 55% P268F 55% T381S 55% A387L 55% W388F 55% Y103W 55% A294Q 55% I332M 55% I171V 55%

What it assembles into

Oligomeric stateChainsEntriesShare
hexameric6 332 38.3%
trimeric3 140 16.2%
pentameric5 72 8.3%
tetrameric4 41 4.7%
dimeric2 36 4.2%
dodecameric12 33 3.8%
monomeric1 17 2.0%
nonameric9 15 1.7%

312 entries have the depositor's assembly corroborated by PISA, 529 carry the depositor's word alone and 18 were assigned by PISA where the depositor gave none. The middle figure is not a disagreement: PISA may have returned nothing or never run. 1 entries carry more than one assembly with different chain counts, so they have no single answer to quote: 6GVN.

Domain architecture

Every source's own domains on the seed axis, one row each. They are not merged: Pfam, CATH, SCOP and InterPro disagree about boundaries, and a merged track would state a consensus none of them gave.

CATHTubulin/FtsZ, GTPase domaiTubulin/FtsZ, C-terminal dHelix hairpin binSCOP2BTubulin nucleotide-bindingTubulin nucleotide-bindingTubulin nucleotide-bindingTubulin nucleotide-bindingTubulin C-terminal domain-Tubulin C-terminal domain-Tubulin C-terminal domain-Tubulin C-terminal domain-1225451
DomainSourceSpan (seed)Chains
Tubulin/FtsZ, GTPase domainCATH 3.40.50.1440 1–259 598
Tubulin/FtsZ, C-terminal domainCATH 3.30.1330.20 269–376 590
Helix hairpin binCATH 1.10.287.600 377–430 482
Tubulin nucleotide-binding domain-likeSCOP2B 8044258 1–243 125
Tubulin nucleotide-binding domain-likeSCOP2B 8034386 2–243 275
Tubulin nucleotide-binding domain-likeSCOP2B 8034383 2–245 261
Tubulin nucleotide-binding domain-likeSCOP2B 8044257 2–245 30
Tubulin C-terminal domain-likeSCOP2B 8034387 244–427 275
Tubulin C-terminal domain-likeSCOP2B 8036011 244–427 125
Tubulin C-terminal domain-likeSCOP2B 8034385 246–438 261
Tubulin C-terminal domain-likeSCOP2B 8036009 246–439 30

What binds it

GTP GTP772 entries GDP GDP681 entries ACP ACP273 entries TA1 TA1133 entries G2P G2P60 entries ANP ANP55 entries ADP ADP52 entries LOC LOC17 entries AF3 AF317 entries ATP ATP15 entries GSP GSP9 entries VYT VYT8 entries
ComponentClassNameEntriesBest (Å)
GTPcofactor Guanosine-5'-Triphosphate 772 1.25
MGion Magnesium Ion 730 1.52
GDPcofactor Guanosine-5'-Diphosphate 681 1.25
CAion Calcium Ion 325 1.70
MESbuffer 2-(N-Morpholino)-Ethanesulfonic Acid 289 1.80
ACPcofactor Phosphomethylphosphonic Acid Adenylate Ester 273 1.80
TA1ligand Taxol 133 2.35
GOLcryoprotectant Glycerol 101 1.80
G2Pligand Phosphomethylphosphonic Acid Guanylate Ester 60 2.26
ANPcofactor Phosphoaminophosphonic Acid-Adenylate Ester 55 2.41
ADPcofactor Adenosine-5'-Diphosphate 52 2.00
CLion Chloride Ion 42 1.80
ZNion Zinc Ion 32 2.60
SO4ion Sulfate Ion 32 1.90
IMDbuffer Imidazole 31 1.90
LOCligand N-[(7s)-1,2,3,10-Tetramethoxy-9-Oxo-6,7-Dihydro-5h-Benzo[D]hepta 17 1.90
AF3ligand Aluminum Fluoride 17 2.21
ATPcofactor Adenosine-5'-Triphosphate 15 2.90
NAion Sodium Ion 10 1.25
EDOcryoprotectant 1,2-Ethanediol 10 1.90

How it crystallises

Parsed from the free text 427 depositors typed into _exptl_crystal_grow.pdbx_details, out of 431 entries that recorded anything at all. Median pH 6.7 (range 5.5 to 9.0).

Precipitants

Magnesium chloride × Calcium chloride × PEG × PEG (unspecified) × Ammonium sulfate × Sodium citrate × Lithium sulfate × Sodium chloride × Tacsimate ×

Buffers

MES × Imidazole × Tris × Bis-Tris × Citrate × HEPES × Sodium acetate × Bis-Tris propane ×

Which entries to trust

838 entries carry a wwPDB validation report: 525 clean, 211 worth a check and 102 with something to explain. Median clashscore 6.57, median RSRZ outliers 3.72%, median R-free minus R-work 0.041. 831 have released structure factors.

Across species

OrganismEntriesBest (Å)Ligand-boundSeed covered
Bos taurus307 1.52 590 100%
Sus scrofa305 1.92 568 100%
Homo sapiens88 1.80 114 100%
Ovis aries38 1.90 75 100%
Mus musculus25 3.19 34 100%
Tetrahymena thermophila11 1.75 22 100%
Chlamydomonas reinhardtii10 3.10 20 100%
Drosophila melanogaster9 2.20 18 99%
Saccharomyces cerevisiae9 2.81 9 98%
Sus barbatus7 2.19 13 100%
Saccharomyces cerevisiae S288C8 2.88 12 98%
Candidatus Odinarchaeum yellowstonii11 1.25 10 96%

Seed sequence

451 residues, numbered every ten. Every identity figure in this document is measured against this sequence.

active or binding site modified residue or glycosylation disulphide cysteine transmembrane or signal the 15 most-substituted positions

1MRECISIHVG QAGVQIGNAC WELYCLEHGI QPDGQMPSDK TIGGGDDSFN TFFSETGAGK
61HVPRAVFVDL EPTVIDEVRT GTYRQLFHPE QLITGKEDAA NNYARGHYTI GKEIIDLVLD
121RIRKLADQCT GLQGFLVFHS FGGGTGSGFT SLLMERLSVD YGKKSKLEFS IYPAPQVSTA
181VVEPYNSILT THTTLEHSDC AFMVDNEAIY DICRRNLDIE RPTYTNLNRL IGQIVSSITA
241SLRFDGALNV DLTEFQTNLV PYPRIHFPLA TYAPVISAEK AYHEQLSVAE ITNACFEPAN
301QMVKCDPRHG KYMACCLLYR GDVVPKDVNA AIATIKTKRT IQFVDWCPTG FKVGINYQPP
361TVVPGGDLAK VQRAVCMLSN TTAIAEAWAR LDHKFDLMYA KRAFVHWYVG EGMEEGEFSE
421AREDMAALEK DYEEVGVDSV EGEGEEEGEE Y

Sites are UniProt's curated features where the seed is a UniProt accession; the substituted positions are measured from this family's own alignment rather than annotated, and only the fifteen most substituted are marked: every position carrying a minority substitution would be most of the protein, because the family holds orthologues. A residue can carry more than one and is drawn with the first that applies, in the order of the key above.

Primary citations

One record per paper, not per entry.

YearCitation
2026 An evolution-conserved allosteric network in human tubulin governs paclitaxel efficacy. Nat.Chem.Biol. doi:10.1038/s41589-026-02204-2
2026 Structure and dynamics of a four-protofilament microtubule from Heimdallarchaeales alpha / beta-tubulin. Sci Adv doi:10.1126/sciadv.aeh4305
2026 Bacteria deliver a microtubule-binding protein into mammalian cells to promote colonization. Science doi:10.1126/science.adz2737
2026 Structure-based design and synthesis of KX-01 analogs as potent antitumor agents targeting the tubulin colchicine binding site. Eur.J.Med.Chem. doi:10.1016/j.ejmech.2026.118849
2026 Cryo-EM structure of the human Hec1-Nuf2 dimer bound to the paclitaxel-stabilized microtubule Sci Adv
2026 Microtubules in the axon are GDP bound but adopt a stable GTP-like expanded state. Nat.Struct.Mol.Biol. doi:10.1038/s41594-026-01787-7
2026 A cryo-EM processing pipeline for microtubules using CryoSPARC. Acta Crystallogr D Struct Biol doi:10.1107/S2059798326003062
2026 Molecular insight into microtubule nucleation by the XMAP215/ gamma-TuRC module. Nat Commun doi:10.1038/s41467-026-72370-3
2026 Adaptations in Plasmodium tubulin determine distinct microtubule architectures, mechanics and drug susceptibility. Nat Commun doi:10.1038/s41467-026-70181-0
2026 Structure-based design and synthesis of 3-substituted-1,2,4-triazolo[1,5-a]pyrimidines as dual vinca/gatorbulin-site ligands for cancer treatment. Eur.J.Med.Chem. doi:10.1016/j.ejmech.2025.118245
2026 Pathogenic KIF1A R350 mutations disrupt a conserved and conformation-dependent kinesin-tubulin salt bridge. Nat Commun doi:10.1038/s41467-026-71026-6
2026 Atomic models of the Toxoplasma cell invasion machinery. Nat.Struct.Mol.Biol. doi:10.1038/s41594-025-01728-w
2026 SPACA9 and MNMIP1 bridge the seam of spermatid manchette microtubules. Embo J. doi:10.1038/s44318-026-00833-w
2026 Structural analysis of a motor with increased mechanical output reveals new transitions in kinesin microtubule motility. Sci Rep doi:10.1038/s41598-025-28573-7
2026 Hierarchical assembly of native cytoplasmic lattices revealed by cryo-EM Vita doi:10.15302/vita.2026.04.0030
2026 Structural basis of microtubule-mediated signal transduction. Cell doi:10.1016/j.cell.2025.11.011
2026 Cytoplasmic lattices store developmentally poised degradative and cytoskeletal complexes in mammalian eggs. Nat.Struct.Mol.Biol. doi:10.1038/s41594-026-01843-2
2026 Structural basis of human gamma TuRC closure during CM1-activated microtubule nucleation. Nat Commun doi:10.1038/s41467-026-70773-w
2026 Doublet microtubule-associated tektins and enzymes differentially regulate sperm flagellar integrity and motility. Nat Commun doi:10.1038/s41467-026-69714-4
2026 Structure of the mouse cytoplasmic lattice. Nature doi:10.1038/s41586-026-10442-6
2026 Cytoplasmic lattices are megadalton storage complexes in mammalian oocytes. Nature doi:10.1038/s41586-026-10513-8
2026 Molecular basis of oocyte cytoplasmic lattice assembly. Nature doi:10.1038/s41586-026-10360-7
2026 In-situ cryo-ET of mouse embryos reveals cytoplasmic lattices contain ubiquitin-charged E2-E3 ligase assemblies. Embo J. doi:10.1038/s44318-026-00895-w
2026 In situ structure of the human ciliary transition zone links linker defects to primary ciliary dyskinesia. Science doi:10.1126/science.aei5957
2025 Structure of quercetin 3,4'-dimethyl ether in complex with tubulin provides a rationale for drug design. Biochem.Biophys.Res.Commun. doi:10.1016/j.bbrc.2025.152245
2025 Structural dissection of alpha beta-tubulin heterodimer assembly and disassembly by human tubulin-specific chaperones. Science doi:10.1126/science.ady2708
2025 Effective Tubulin Degradation by Rationally Designed Proteolysis Targeting Chimeras Biorxiv doi:10.1101/2025.05.22.655572
2025 Design and synthesis of novel 4-aryl-2-benzoyl-imidazoles as colchicine binding site inhibitors. Eur.J.Med.Chem. doi:10.1016/j.ejmech.2025.118021
2025 Discovery of Kinesin KIF18A Inhibitor ATX020: Tactical Application of Silicon Atom Replacement. Acs Med.Chem.Lett. doi:10.1021/acsmedchemlett.5c00512
2025 KY216-tubulin complex captures VASH2 to inhibit NSCLC metastasis. Nat Commun doi:10.1038/s41467-025-66817-2
2025 Identification of a ligand-binding site on tubulin mediating the tubulin-RB3 interaction. Proc.Natl.Acad.Sci.USA doi:10.1073/pnas.2424098122
2025 Trypanosome doublet microtubule structures reveal flagellum assembly and motility mechanisms. Science doi:10.1126/science.adr3314
2025 Evolutionary adaptations of doublet microtubules in trypanosomatid parasites. Science doi:10.1126/science.adr5507
2025 Microtubule association induces a Mg-free apo-like ADP pre-release conformation in kinesin-1 that is unaffected by its autoinhibitory tail. Nat Commun doi:10.1038/s41467-025-61498-3
2025 Mechanistic basis of temperature adaptation in microtubule dynamics across frog species. Curr.Biol. doi:10.1016/j.cub.2024.12.022
2025 How augmin establishes the angle of the microtubule branch site. Nat Commun doi:10.1038/s41467-025-64650-1
2025 Tubulin acetyltransferases access and modify the microtubule luminal K40 residue through anchors in taxane-binding pockets. Nat.Struct.Mol.Biol. doi:10.1038/s41594-024-01406-3
2025 In situ structural mechanism of epothilone-B-induced CNS axon regeneration. Nature doi:10.1038/s41586-025-09654-z
2025 Dimerization of GAS2 mediates crosslinking of microtubules and F-actin. Embo J. doi:10.1038/s44318-025-00415-2
2025 Mechanistic insights into TTLL11 polyglutamylase-mediated primary tubulin chain elongation. Sci Adv doi:10.1126/sciadv.adw1561